What's the missing number?

Math it's appreciated. (picture provided)

Acolony contains 1500 bacteria. the population increases at a rate of 115% each hour. if x represents the number of hours elapsed, which function represents the scenario? f(x) = 1500(1.15)" f(x) = 1500(115) f(x) = 1500(2.15) f(x) = 1500(215)

Pyramid shown has a square base that is 18 inches on each side has a surface area of 164 square inches what is the slant height